1. Field of the Invention
This invention relates to a liquid crystal display, and more particularly to a method and apparatus for driving a liquid crystal display that is adaptive for reducing the number of data lines.
2. Description of the Related Art
Generally, a liquid crystal display (LCD) controls a light transmittance of a liquid crystal using an electric field to display a picture. To this end, the LCD includes a liquid crystal display panel having a pixel matrix, and a driving circuit for driving the liquid crystal display panel. The driving circuit drives the pixel matrix such that picture information can be displayed on the display panel.
FIG. 1 shows a related art liquid crystal display device.
Referring to FIG. 1, the conventional LCD includes a liquid crystal display panel 2, a data driver 4 for driving data lines DL1 to DLm of the liquid crystal display panel 2, and a gate driver 6 for driving gate lines GL1 to GLn of the liquid crystal display panel 2.
The liquid crystal display panel 2 has thin film transistors TFT each of which is provided at each crossing between the gate lines GL1 to GLn and the data lines DL1 to DLm, and liquid crystal cells connected to the thin film transistors TFT and arranged in a matrix.
The gate driver 6 sequentially applies a gate signal to each gate line GL1 to GLn in response to a control signal from a timing controller (not shown). The data driver 4 converts data signals for red (R), green (G), and blue (B) from the timing controller into analog video signals to thereby apply video signals for one horizontal line to the data lines DL1 to DLm each one horizontal period when a gate signal is applied to each gate line GL1 to GLn.
The thin film transistor TFT applies data from the data lines DL1 to DLm to the liquid crystal cell in response to a control signal from the gate lines GL1 to GLn. The liquid crystal cell can be equivalently expressed as a liquid crystal capacitor Clc because it has a common electrode opposite a pixel electrode each other having liquid crystal therebetween. The pixel electrode is connected to the thin film transistor TFT. Such a liquid crystal cell includes a storage capacitor (not shown) connected to a pre-stage gate line in order to keep data voltage charged in the liquid crystal capacitor Clc until the next data voltage is charged therein.
The liquid crystal cells of the related art LCD has vertical lines equal to the number (i.e., m) of the data lines DL1 to DLm because pixels are provided at crossings between the gate lines GL1 to GLn and the data lines DL1 to DLm. In other words, the liquid crystal cells are arranged in a matrix in such a manner as to make m vertical lines and n horizontal lines.
The conventional LCD requires m data lines DL1 to DLm so as to drive the liquid crystal cells having m vertical lines. Therefore, the conventional LCD has a drawback in that a number of data lines DL1 to DLm should be provided to drive the liquid crystal display panel 2. Hence, process time and manufacturing resources are wasted. Furthermore, the conventional LCD has a problem in that, since a large number of data driving integrated circuits (IC's) are included in the data driver 4 so as to drive the m data lines DL1 to DLm, the manufacturing costs are high.